Table 2.
Association of HNSCC with smokeless tobacco use.
| Variables | Case (%) | Control (%) | OR1 | 95% CI1 | OR2 | 95% CI2 |
|---|---|---|---|---|---|---|
| Smokeless tobacco use history | ||||||
| Never | 1,003 (96.91) | 1,200 (98.20) | 1.00 | --- | 1.00 | --- |
| ≥ 20 times | 32 (3.09) | 22 (1.80) | 1.63 | 0.94, 2.85 | 1.20 | 0.67, 2.16 |
| Duration of smokeless tobacco use in lifetime (y) | ||||||
| Never | 1,003 (96.16) | 1,200 (97.32) | 1.00 | --- | 1.00 | --- |
| > 0 to < 2 | 6 (0.58) | 10 (0.81) | 0.71 | 0.26, 1.97 | 0.63 | 0.22, 1.77 |
| ≥ 2 to <10 | 18 (1.73) | 19 (1.54) | 1.09 | 0.56, 2.09 | 0.83 | 0.41, 1.66 |
| ≥ 10 | 16 (1.53) | 4 (0.32) | 4.43 | 1.47, 13.36 | 4.06 | 1.31, 12.64 |
| p for trend | 0.008 | 0.021 | ||||
| Average frequency of smokeless tobacco use per week (times) | ||||||
| Never | 1,003 (96.44) | 1,200 (97.48) | 1.00 | --- | 1.00 | --- |
| > 0 to < 7 | 16 (1.54) | 19 (1.54) | 0.97 | 0.50, 1.91 | 1.00 | 0.50, 2.00 |
| ≥ 7 to < 14 | 12 (1.15) | 8 (0.65) | 1.66 | 0.67, 4.11 | 1.23 | 0.48, 3.14 |
| ≥ 14 | 9 (0.87) | 4 (0.32) | 2.51 | 0.77, 8.21 | 1.39 | 0.39, 4.89 |
| p for trend | 0.100 | 0.572 | ||||
| Lifetime numbers of smokeless tobacco use (times/wk*y) | ||||||
| Never | 1,003 (96.54) | 1,200 (97.80) | 1.00 | --- | 1.00 | --- |
| > 0 to < 20 | 12 (1.15) | 16 (1.30) | 0.87 | 0.41, 1.85 | 0.93 | 0.43, 2.01 |
| ≥ 20 | 24 (2.31) | 11 (0.90) | 2.43 | 1.18, 5.02 | 1.72 | 0.81, 3.68 |
| p for trend | 0.016 | 0.159 | ||||
1
OR adjusted for age and gender.
2
OR adjusted for age, gender, race (White, non-White), education (3 categories), smoking (continuous), ever smoker, alcohol drinking (continuous).